The invention relates to an adjustable seat, and method for controlling same, having a backrest and a seat cushion. A plurality of adjusting elements are arranged in the backrest inside the contact surface of the backrest facing a user. The adjusting elements can carry out a lifting movement directed approximately perpendicularly to the contact surface.
A seat having a backrest is known from U.S. Pat. No. 5,558,398, which seat has a plurality of lifting elements arranged, in pairs, symmetrically with respect to a vertical axis of the backrest.
Furthermore, International patent document WO 2004/026623 A1 describes a seat having a plurality of elements in the backrest and seat cushion, which elements can be acted upon by pressure and by which the seat contour can be influenced for achieving various massaging effects.
It is an object of the invention to further develop a seat of the type known from U.S. Pat. No. 5,558,398 in the sense of an improved mobilization, particularly of the seat user's back.
This object is achieved by a seat according to the invention having a backrest and a seat cushion. A plurality of adjusting elements are arranged in the backrest inside the contact surface of the backrest facing a user. The adjusting elements can carry out a lifting movement directed approximately perpendicularly to the contact surface. A control is provided, by which the adjusting elements, in a mutually time-coordinated sequence, are activated such that a rotational movement is applied to the user's back, which rotational movement is comparable to the rotational movement during walking.
According to the invention, adjusting elements in the backrest of the seat are arranged and designed such that they can carry out a lifting motion in a direction approximately perpendicular with respect to the seat user's contact surface. The adjusting elements are provided on certain regions of the seat back in order to achieve active motion of the back there by a targeted adjustment onto the seat user. The adjusting elements are arranged on the right and the left of the seat user's spinal column, preferably symmetrically with respect to the longitudinal center plane of the backrest. In each case, two adjusting elements are provided in the upper region of the backrest, thus in the region which is situated opposite the seat user's shoulder. These two adjusting element in the shoulder region are supplemented by two central adjusting elements in the seat user's chest region and/or by two adjusting elements in the lower region of the backrest, which is situated opposite a seat user's lumbar region. As a result of the arrangement of the adjusting elements in the described regions of the backrest according to the invention, which regions correspond to certain regions of the seat user's back, by means of the lifting motion of the adjusting elements, a targeted active movement of the back (as well as individual spinal column sections or vertebrae segments of the back) can be achieved, as described in detail in the following.
As a result of the control method according to the invention, the adjusting elements are activated such that the seat user's back is rotatorily mobilized. This active rotatory mobilization causes a movement of the person's back that corresponds to the movement of the spinal column while walking. This thus simulates a natural motion sequence which, as a result of the person's static posture, cannot be actively carried out by a seat user himself. By means of the rotating movement exercised upon the back by the adjusting elements, the phenomena of fatigue and tension can be counteracted extremely effectively.
If there is a sufficient lifting path, the adjusting elements cause a mobilization of individual vertebrae with respect to one another or a mobilization of vertebra segments. The acted-upon vertebrae or the acted-upon vertebrae segment experiences a micro movement with respect to the adjacent vertebra or vertebra segment. This micro movement is known from the “manual therapy” of the spinal column in medicine and is successfully used for mobilizing vertebrae and vertebra segments in order improve movement, which becomes noticeable as an improvement of comfort.
The rotatory mobilization is preferably achieved by four or six adjusting elements in the backrest, which rotate the seat user's back. As described above, the adjusting elements in the shoulder region together with the adjusting elements in the thoracic and/or lumbar region are appropriately controlled.
In a preferred embodiment of the invention, the adjusting elements are arranged in the lateral edge regions of the backrest such that they can actively move the seat user's back in a region situated as far as possible to the outside, in order to achieve a lever effect as large as possible. Naturally, the adjusting elements are to be placed such that they can also still operate effectively in the case of smaller and narrower seat users.
In an advantageous further development of the invention, the adjusting elements in the backrest are supplemented by adjusting elements in the seat cushion, as known per se from German patent document DE 197 26 409 A1. This document describes a seat cushion with two adjusting elements which carry out a lifting movement in a direction approximately perpendicular to the surface of the seat cushion. The adjusting elements are moved in an alternating fashion and thereby generate a tilting movement of the seat user's pelvis similar to the movement of the pelvis while walking.
As a result of this combination of adjusting elements in the backrest and the seat cushion, in connection with a corresponding control, a three-dimensional rotational movement of the back and the pelvis is achieved. The adjusting elements in the backrest together with the adjusting elements in the seat cushion carry out an adjusting movement in opposite directions. This supplementation of the rotational movement of the back by the tilting movement of the pelvis is particularly advantageous for a mobilization of the seat user's spinal column as a whole. This rotatory mobilization is a simulation of the rotational movement which the back and the pelvis carry out when a person is walking.
In the described embodiment of the invention, four or six adjusting elements are therefore provided in the backrest of the seat and at least two additional adjusting elements are provided in the seat cushion. Naturally, a number of adjusting elements deviating therefrom may also be constructed in the seat.
Adjusting elements of a different size, a different mechanical construction, and/or of a different geometry may be used.
In principle, the adjusting elements are symmetrically arranged in the right and left half of the seat. However, deviating therefrom, an asymmetrical distribution of the adjusting elements at least in sections is also contemplated, depending on the further development of the seat.
The adjusting elements are preferably arranged between the basic springs, i.e., the force-absorbing structure of the seat, and the cushioning of the seat, as a rule, a foam material. As a result of this placement of the adjusting elements between the frame and the seat foam, the adjusting elements are prevented from acting in a comfort-reducing spot-type manner upon the seat user's back and, possibly, also upon his posterior. To the contrary, as a result of the described arrangement, a pressure distribution is achieved over a larger surface while the adjusting elements do not act upon the seat user's body in an excessively punctiform manner. However, the described arrangement of the adjusting elements simultaneously ensures a sufficiently precise localized force effect upon the seat user's back and possibly his posterior.
Supplementary to the adjusting elements, another embodiment of the invention provides a plurality of massaging elements arranged above one another in the backrest, as known per se from German patent document DE 38 30 235 C2 or DE 201 08 345 U1. In the case of DE 38 30 235 C2, the massage elements are controlled such that, as a result of a progressive action upon adjacent massaging elements, a roller-type wave motion is created that runs through along the vertical dimension of the backrest.
The wave motion applied to the seat user's back provides a massage of the muscular system along the spinal column, predominantly of the muscles next to the spinal column. As a result of this direct mechanical effect on the muscular system, the blood circulation of the muscular system of the back is increased with the result of a regeneration and a subsequent relaxation of the muscle system, including the surrounding body structures (cartilage, ligaments, tendons). In addition, the spinal column is slightly moved, in the sense of a periodic straightening of the back, as a result of the applied wave motion. This movement of the spinal column increases the positive effects of the rotatory mobilization in that, here also, changing pressures are generated upon the intervertebral disks, with the result of an improved supply to the intervertebral disk cartilage.
The seat according to the invention can be used particularly advantageously in motor vehicles because here the user, in many cases, remains statically seated for extended periods of time. And, because of the circumstances existing in a vehicle, in the case of the driver, an active movement by the driver is not possible as a result of the traffic situation. As a result of the rotatory mobilization, the spinal column is moved in a manner corresponding to the natural course of movement when walking. This movement has the result that changing pressures are created upon the intervertebral disks, which promote the supply of nutrients to the intervertebral disk cartilage by way of a diffusion process. This changing load upon the intervertebral disks therefore promotes their regeneration. The rotatory mobilization also acts upon the muscular system, so that muscular tenseness is successfully avoided or at least reduced.
The lifting movements of the adjusting elements should be restricted in order to preclude such movements from being inadvertently transmitted to the steering wheel by way of the driver's arms, which would negatively influence driving activities. In addition to this direct introduction of movements by way of the driver's arms, it should also be observed when proportioning the lifting movements that the movement receptors in the driver's arms are not addressed, so that no distraction is caused during driving.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.